I'm moderately sure that there's a part of private equity that would be content with a steady profit (at the right price). It's just not the part that you usually hear about.
Private equity is often mining a company for money for a few years before discarding it or rolling it up with something. Quick results, not long term stability & growth. Profitable income from the company is not always a goal, often the money is to be made in asset stripping, financial engineering, management fees, etc... then reducing with layoffs, underinvestment, vendor abuse, etc... until nothing is left but a husk that is profitable enough on paper that it can be sold on.
The path to "get rich quick" is selling a lot of cheap junk for a high price. In order to make this work you need to constantly be on the lookout for a new scheme though as the money will run out on the old one fast.
The get rich not quick as quick (and perhaps not quite as rich) it make a good quality product with consistent margins as you earn a reputation.